I picked up this vertical twin cylinder air compressor from an estate sale. I can find no manufacturer marks anywhere on the pump. Everything on the unit looks original and the pressure switch works fine, but it does look like there has been some repair work on the top of the crankcase, JB weld or something; repair looks old so I'm not messing with that. I do need to replace or work on the discharge valves as pressure is leaking back into the cylinders and the unit won't cycle back on after the pressure switch tells the unit to come back on; too much pressure bleeds back into the cylinder and the motor just smokes the belt. Once I bleed the tank pressure off, the unit works fine and pumps back up to 100psi. I need some help identifying the pump so I can rebuild the top end. Thanks!

Other than that, all I can suggest is a Google of compressors, perhaps with modifiers like stationary and/or reciprocal, and put it to images to see what you can see.

At 65 or so, not likely you'll find it, and of course even if you do it's gonna be unlikely they still have parts for it, like some places have car parts.

In short, you'll most likely have to make or have made any parts you need short of standard screws and the like.

Good luck - you'll need it.

Aug 27, 2014

One more question...the important one...by: R. Douglas

Hey Doug in s.d.ca.,

Do you have any opinions as to the make of my air compressor in the photos? One day I am going to need parts, and I have no clue as to the make, let alone the model of this animal. Thanks!

Aug 26, 2014

sizing checkby: Doug in s.d.ca

Yeah, stuff breaks...

As to sizing, most checks I've come across operate with just a pound or two of forward pressure, and ratings of total pressure mostly start at around 500 PSI...so pretty much anything with the right pipe size will work.

McMaster-Carr has quite an assortment if you don't find it locally. And their on-line catalog is wonderful. You should try it even if you don't buy.

Aug 26, 2014

Problem was the check valveby: R.Douglas

Thanks Doug from s.d.ca.,

You were right on the money, the problem was the tank check valve. I removed it and it had trash in it and a damaged 65 year old spring (the unit is a 1949 model) I cleaned the original check valve and it will re-start now at 40 psig but not any higher, I will have to replace with a new check. Do I size the check based on the high pressure setting on the pressure switch or the limit of the tank? High pressure on the switch is set at 100 psig. I won't being running pressures higher than that.

Aug 25, 2014

Compressor from estate saleby: R. Douglas

Thanks for your input. I was just reading and learning last night about the importance of unloader valves and check valves so I'm thinking I will dive into your scenario first. I appreciate you weighing in on this. I will keep you in the loop as things progress.

Aug 24, 2014

check valveby: Doug in s.d.ca

Perhaps I am misreading what you wrote, but if not, then probably all you need to do is fix a leaky (or stuck open) tank check valve.That looks like it's part of the thing under the pressure switch, PRV, and gage: or it might be in the line off the head direct into the tank, can't tell for sure in the pix.

Once that's done, you should be OK, barring a possibly too-loose drive belt, which may still slip a bit on restart after you fix the valve.